This is (obviously) a pejorative term. If the flow of a game is turning to heavily benefit one team, often a player for the other team with a mild injury will ham it up a little when he gets hit by an opposing player. In addition to garnering a foul call, or possibly a card, play will stop for a period of minutes if the player has to be removed on a stretcher by a team of medical personnel.

Once the player is off the pitch and on the sidelines, play will resume, but the momentum of the opposing team usually has been lost in the idle time. The injured player will soon thereafter ask and receive permission to re-enter the field from the referee, somehow magically revived by simply being carried off on a plastic pallet with handles.